How To Build An 850+ Horsepower 7.3L

An Inside Look At Swamp’s Diesel’s Trick Power Stroke

Building big power with a diesel is not hard, unless you start to get close to the upper end of the envelope. It’s at that point where the trick parts and pieces are used, along with some secret tricks of the trade privy only to top-notch engine builders.

This month, the folks at Swamp’s Diesel Performance in LaVergne, Tennessee, gave us the behind-the-scenes exclusive on how they build their 850-horsepower 7.3L competition engines and what they go through before being shipped out to customers. Not only did we see one of these 800+ horsepower beasts run on the engine dyno, we also went behind closed doors into the engine assembly department to check out the parts and pieces that go into one of Swamp’s competition engines.

1 Jonathan “Swamp” Ryan is the head of R&D at Swamp’s Diesel Performance and he operates the shop’s dyno cell from his command center while the engine runs behind safety glass in front of his monitor bank.

2 They have all the electronics required to run the engine right there on the dyno along with additional sensors to monitor every aspect of engine performance for diagnostics and performance evaluation.

3 The heart of one of their competition engines is the reground and polished factory crankshaft.

4 Forged billet steel Manley connecting rods are used in their standard competition engines with the option to use Crower or Carrillo rods for an additional charge.

5 The forged rods swing Mahle pistons that are treated to valve reliefs as well as ceramic coating on the tops and DFL coating on the skirts.

6 Johnny Farrow builds the bottom end of his competition engines to last, using a girdle and ARP main studs to secure the balanced rotating assembly in the block and prevent the block from flexing or deforming under power.

Jonathan “Swamp” Ryan is the head of R&D and dyno operator at Swamp’s and he walked us through their engine dyno cell and control station, including all the isolation and safety mechanisms, then fired up the engine to bring it up to operating temperature. The dyno cell has everything the engine needs to run in a truck right there in the room, including ECM, FICM, radiator, intercooler, intake and exhaust all mounted on a stationary stand and linked to a large water brake to provide a load for the engine. Ryan is able to start, control and monitor the engine from outside the dyno cell through computer interfaces and both analog and digital gauges. He even monitors the exhaust outlet high above the building with a webcam.

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7 To control crankshaft harmonics, Swamp’s uses Fluidampr dampers on their competition engine builds.

8 They have the camshafts custom ground to best suit your application, then polished before installed with new bearings.

9 New pushrods are used to hold up to the stiffer springs and to handle high boost pressures in the combustion chamber without bending.

10 & 11 Both the exhaust and intake runners are ported and polished for better flow in and out of the cylinder head.

Each and every competition engine they build and sell is flogged on the dyno not only to ensure that it’s performing up to performance expectations, but also to ensure that without a doubt the engine is running properly and trouble free. Ryan is very hard on the engines on the dyno so that Swamp’s can be confident that they’re selling engines that are tried, tested and built to last. They even back the Competition Engines with a one-year warranty, something that very few builders do, especially with performance engines destined to be used in race and competition applications.

Swamp’s engine department head Johnny Farrow walked us through the components that he uses when assembling one of these monster 7.3L engines and let us peek in on the assembly of one of them. He hand selects blocks and heads that pass rigorous testing, including measurements and magnafluxing to make sure there are no cracks, flaws or defects, as the foundation for each competition engine build.

12 The assembled head uses new valves, guides and seals as well as new beehive springs, retainers and locks to make sure the engine can handle high-rpm operation. They’ve been tested beyond 5,500 rpm!

13 To keep the fire-ringed heads firmly in place the Swamp’s build team uses A1 Technologies H11 head studs.

14 Farrow torques the head studs when assembling the engine, and then retorques them after break-in and once more after a heat cycle.

15 & 16 The Swamp’s Diesel Performance Gen3 HPOP works with the factory HPOP and is guaranteed to be capable of keeping up with any size injector available.

Once the blocks pass those tests they are filled with HardBlok and fitted with BHJ deckplates and main caps and girdles before they’re machined to true the crank shaft centerline and cylinder bores and make sure that the block does not dimensionally change while the filler cures. The top two inches of the block are left unfilled for coolant circulation where combustion occurs in the hottest part of the block. The block and head sealing surfaces are trued to a flatness and smoothness level that far exceeds the factory tolerance for superior sealing.

While the two-week filling, curing and machining process is taking place on the block, Farrow and his team go to work on the cylinder heads. They are machined for new valve guides and to accept fire ring head gaskets, then the intake and exhaust parts are hand ported and polished to maximize airflow within the head. After Stage 2 machining and porting, the heads are reassembled with new cast iron valve stem guides, new SBI intake and exhaust valves with a multi-angle valve job, Stage 2 beehive valve springs, seat retainers and locks, as well as new Motorcraft injector cups and glow plugs.

17 Ceramic-coated tubular stainless steel headers are included with each competition engine to help the engine exhale better and take advantage of the exhaust runner porting in the cylinder head.

18 Ryan flogs every competition engine on the dyno before it’s delivered to the customer to make sure that it’s built up to the lofty Swamp’s Diesel Performance standards. Notice the monitors that show engine performance as well as views of the engine in the dyno cell and the exhaust output on the roof of the building.

Inside the engine, the Swamp’s team uses Manley billet steel connecting rods attached to a reground and polished crankshaft that swings a set of Mahle aluminum pistons sealed with Mahle rings. The pistons are machined for valve clearance and feature ceramic-coated tops as well as dry film lubrication-coated piston skirts. The entire rotating assembly is measured (to the nearest ten-thousandth of an inch), weight matched and balanced to ensure smooth and trouble-free performance. A Fluidampr harmonic balancer is included as well.

Of course, new gaskets are used when assembling the engine along with Federal Mogul rod and main bearings, and Motorcraft cam bearings for the custom ground and polished camshaft. They use a plate girdle and ARP main studs on the bottom end as well as A1 Technologies H11 tool steel head studs to hold everything together securely to make big power and withstand the tremendous loads and pressure inside the engine. A Melling high-volume oil pump is used to make sure that the low-pressure side of the engine maintains lubrication.

The engines are finished with high-temp engine paint in black or other optional custom colors available. New Motorcraft sensors, harnesses, oil pan, pickup tube and water pump round out the Competition Engine package while stainless steel tubular headers are included to get the spent gasses out of the ported heads quickly and efficiently.

19 After the dyno pulls the headers show a little bit of heat!

20 The shop might have a little redneck in it with its stack blowing smoke high into the air during dyno runs.

21 Farrow (left) and Chey Engel swap out the turbo charger for some more R&D test pulls; they have room to easily work on the engine right in the dyno cell to make changes and adjustments when testing various performance parts.

22 Looking at a composite dyno graph with four runs on the same graph shows how consistent engine output is with one of their competition engines.

23 Comparing the latest Forced Inductions 80/88 turbo with its 2.8 class cover to their old test mule turbo with its 3.2 class cover shows that the new turbo is even more efficient making both more power and torque across the entire power band.

24 Inside the dyno cell is everything but the chassis and cab of a running truck to allow them to measure accurate results when dynoing engines.

After the clean room assembly is completed, each engine undergoes a break in process on the dyno where it’s brought up to operating temperature and then moderately loaded under varying rpms. Then, the fuel injectors are removed and the head studs retorqued and the engine is allowed to cool overnight. Once cool, the head studs are retorqued one more time before the injectors are reinstalled and the engine is run at full load on the dyno.

To get an idea of the exact performance of the engine, the team at Swamp’s recommends that the customer provide the actual injectors, HPOP and turbo or turbos so that they can be run with the engine during the dyno testing. Of course, you can also purchase new high-performance injectors, HPOPs and turbos directly from Swamp’s for one of their complete power packages.

The engine we saw on the dyno was built for Chris Kazarian for his competition truck. It used the Swamp’s Gen3 HPOP along with Swamp’s high-flowing 400cc/400% injectors and a Forced Inductions 80/88 turbo with a 2.8 class race cover to make 872 horsepower and 1,712 lb/ft of torque. Ryan also ran the engine for several dyno pulls with their old test mule 80/88 turbo from River City Turbo with a 3.2 class race cover and it made 857 horsepower with 1,574 lb/ft of torque. If you’re interested in competing with a 7.3L Power Stroke engine, you owe it to yourself to check out the Competition Engines from Swamp’s Diesel Performance. Follow along over these pages to see what goes into one of them. DW

SOURCE

Swamp’s Diesel Performance
Dept. DW
304 Sandhill Road
LaVergne, TN 37086
866-595-8724
www.swampsdiesel.com